Reboring tool



FebQzs, 1930.

A. T. GREEN REBORING TOOL 2 Sheets-Sheet 1 l Filed Feb. 11. 1927 v ATTOR N EY Feb. 25, 1930. A. T. c-zRELN 1,748,876

REBORING TOOL Filed Feb. l1, 1927 2 Sheets-Sheet 2 Y VPatented Feb. v

UNITED STATES ANsEn fr; GREEmoF ABERDEEN, sourir DAKOTA REBORING TOOL*Application filed February 11, 1927.` Serial No. 167,541.

My invention relates to certain novel improvements in reboring tools andmore par,-

Y y ticularly to a reboring tool especially adapted for reboring themain bearings of an internal `5 combustion engine and has for itsprincipal object the provision of an improved construction of thischaracter which will be highly efcient in use. i y i It is a universalcustom in factory assemf10 bly to iit the crank shaft of an internalcombustion engine to its kbearings by a method Vwhich lis commonlytermed burning in the bearings. This is accomplished by assembling theengine and coupling the crank shaft (l5 at a speed proportionate to burnin the bearings. The dihculty encountered with in this method resides inthe fact that due to the 'tight it between the crank shaft and the .mainbearings, thebabbitt is often worked loose of '20 shifted or-otherwisedamaged. Again it is the custom to obtain smoothand knockless iitbetween the main bearings and thek crank shaft providing -a tool whichoperates on the babbitt toy remove such surfacebabbitt as is necessaryto provide. proper vjournal vengagement between the main;bearings,Aincluding their caps, and the crank shaft,'and unless this tool isproperly aligned'the results will be that the bearings and the crankshaft will 30 have what is calledk high spots'resulting in bearingknocks.r :1t isk thereforeA one ofthe ,man'y'objectsof this invention toprovide 'aztool which will accurately bore and rebore the main bearingsof an internal combustion engine-without injury to they babbitty and tohold the boring tool in proper alignment to assure, perfect alignmentbetween the main bearings "and gth'e' cylinder bores assuring I propermesh between thetiming gears.

complish the results as set forth in my- Patent No. 1,585,0261dated May18, 1926, Yby a tool whichk will -assurelabor savii'ig and is ineX- `Vpensively constructed. v. f

. Other objects will appear hereinafter.

n The invention consists Vin the novel combination'and arrangement ofparts to be herefinafter described and claimed.

VThe invention will be besty understool by reference to theaccompanyingv drawings,

' Another `object of the inventionvisvto ac.

showing the preferred form of construction and in'which: i

Fig. l is a plan view of the invention showing thesaine in operativelposition upon an engine block; 1

Fig. `2 is af'cen'tral'longitudinal -vertical sectional detail viewofthesame';` and Fig. 8 is a sectional detail view taken sub- Y vincludescarriage plates 24. These carriage plates 24C have their intermediateportions -arched upwardly as at 25- and. formed on these arched portionsvare bearing sleevesV 26. Thezend portions 27 of the `:carriage plateseach have. formed atherein spaced: parallel extending slots 728zfor'reasons 'hereinafter set forth. Adjustably mounted vinthe bear-V ingsleeves 26 ofthe carriage' plates `24 vare n studs '29 of the boring barsupporting arms `indicated generallyatBO. vThese 'studs 29 are securedin` proper adjustedposition with-k ydiuni of nut receiving bolts '35.

The end portion-:36 of the vboring-bar has threads 37 formed thereon andthese threads i 37 are adapted -to engage lthe threads (not shown) of afeed nut 38 vwhich may be ofan approved 'construction. This/feed nut 38has attached vto aflange 39 thferofa st opbar 40 which is adapted toengage any place on; the

hold-the feedvnut againstr()tagl `I Y l crank case to tion'. l

Movable. longitudinally with respect tofthe boring bar arecollars 45,said collars/having central bores for close fit with 'respect to the 2iA Lmasve ing bar for seating in the'bearing sections.-

The collars when seated in the bearing sections properly center andalign theboring bar with respect to these bearing sectionsV and afterthis has been accomplished the carriage plates flatly rest upon 'the rim19 of the crank case to adjust the studs 29 in the bearing sleeves 26.rIhe carriage plates are now'secured to the rim 19 of the crank casethrough the medium of nut receiving bolts 42 which have their shankportions projecting through certain of the'slots 28 and openings 21, thelatter being formed in the rim 19. The set screws 31 and 33 are nowadliusted to secure the studs 29 within the bearing sleeves 26. Afterthis has been accomplished the collars areremoved from seated positionin the bearing sections and the bearing caps remounted in position andsecured to the engine block through the medium of the bolts 41 of theusual construction. The boring bar 22 is now rotated through the mediumof the handle 42 secured as at 43 to its end portion 44.

From this it will be seen that I provide a simple and elcient means forboring the main bearings of an internal combustion engine block and forcentering and aligning the. boring bar with respect to the bearings andthat the tool comprises' few parts which may be assembled forboring'operation by others than those skilled in the art and that themanner of adjusting the tool in position, by reason of the simplicityofthe device, is practically self-explanatory tothe mechanic.

As the boring bar 44 is rotated the cutting tools 23 will be broughtinto cutting position with respect to the babbitt of the bearingsV andlongitudinal feeding. of the boring bar is Vaccomplished by. the feednut 28 which is held against rotation by the stop bar 40.

Vhile Ihave illustrated and described the preferred form of constructionfor carrying my invention into eect, this is capable of va- Y riationand modification, without departing from the spirit of the invention. I,therefore,

do not wish yto be limitedto the precise details of construction setforth, but desire toV avail myself of such variations and modificationsas come within the scope of the appended claims.

I-Iaving thus described my invention what lI claim as new and desire toprotect by Letters'Patrent is: 1.

1. In a device for boring the main bearings of an internal combustionengine block, a carriage member having elongated foot portions andanupwardly arched portion intermediate said foot portions, said footportions having longitudinally extending slots therein, means extendablethrough said slots for connecting said foot portions'to said block, avbearing structure at substantially the midpoint of saidarched portion,and extended at rightangles to the extent of said arched bore, saidbearing portion having a bore extending therethrough and a recesscommunicating with said bore at one side thereof for a portion of theextent thereof, a stud shaft extended through said bore, a platedisposedl in said recess, means for forcing said plate into engagementwith said shaft to hold said shaft against movement, a bearing structureat the lower end of said stud shaft, and a boring bar rotatably mountedin said last namedl bearing structure.

2. In a device for boring the main bearings of an internal combustionengine block,a carriage member having elongated foot portions and anupwardly arched portion intermediate said foot portions, said footportions having longitudinally yextending relatively elongated slotstherein, means extendable through said slots forV connecting said footportions to said block, a bearing structure at substantially themidpoint in said arched portion having a bore therein extendedsubstantially at rightangles to the extent of said arched portion, saidbearing structure havingv a recess therein communicating with said borefor a portion of the extentthereof, a stud shaft disposed in saidbore, aplate in said recess, screw members carried by said bearing structure.and bearing against said plate to force said plate into engagement withsaid stud shaft to hold said/shaft inpredetermined positions, another.`bearing structure at the lower end of said stud shaft, .a boring barjournaled in said last named bearing structure, meansV for impartingaxial movement tosaid boring bar, and cutting tools on said boring baradjacent the bearings of said block whereby saidfcuttingtools may act onsaid bearings when ,saidvbar is rotated. 4

In testimonyvwhereof I affix my signature.

' ANSEL 'IQ GREEN.

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